1. Field of the Invention
The present invention pertains to pipe connection and disconnection operations. More particularly, the present invention pertains to a weight compensator for use during pipe installation and removal operations. More particularly still, the present invention pertains to a bail assisted assembly for stabbing and connection of tubular members in oil and/or gas wells or other applications.
2. Brief Description of the Prior Art
Pipe and/or other tubular goods are typically installed in oil and/or gas wells for a variety of reasons. In many instances, such pipe and/or tubular goods are inserted into a well in a number of separate sections of substantially equal length called “joints”, or combinations of joints called “stands”, using a drilling rig or other equipment located at the earth's surface. The pipe sections are typically joined end to end using threaded connections to form a continuous length of pipe that extends downward into a well.
As part of the pipe installation process, a first segment of pipe is partially inserted within the upper opening of a wellbore and suspended or hung in place using slips positioned at or near the rig floor. Thereafter, an additional section of pipe is added to the upper end of said suspended first section, and the joined pipe string is then partially lowered deeper into said wellbore. The process is repeated until the overall pipe string has a desired length that extends a desired distance into said wellbore.
When a string of pipe is suspended within a wellbore, a portion of the uppermost section of pipe protrudes out of the upper opening of the well and extends a desired distance above said rig floor and slips. A threaded connection (according to industry convention, typically a female or “box end” threaded connection) is positioned at the upper end of said section of pipe and faces upward for receiving a mating threaded connection from another section of pipe that is to be joined to said string.
Thereafter, a separate section of pipe is typically lifted within a drilling rig derrick using a top drive unit or other hoisting equipment, and suspended vertically within said derrick. Said separate section of pipe is then lowered toward said suspended pipe string until a threaded connection (typically a male or “pin end” threaded connection) at the lower end of said separate section of pipe is stabbed into said threaded connection located on the upper end of said pipe string. In this position, torque can be applied to one or both of said pipe sections in order to join or “make-up” said threaded connection members.
Skill is required to lower said separate pipe section into position to make a threaded connection with the uppermost section of the pipe string suspended in the wellbore. If the separate pipe section is positioned too high above the box end connection of the suspended pipe string, the mating threads will not engage each other. Conversely, if the separate section is lowered too far, the full weight of said section may rest on the threaded connection of the suspended pipe string and damage may occur; further, even if damage does not occur, lowering of said separate pipe section too far can make maneuvering or manipulation of said section difficult.
As a result, during the pipe stabbing and connection process, mating pipe sections/strings should ideally be axially aligned with one another, and the weight of said separate (hanging within a rig derrick) section of pipe should beneficially be compensated or offset to prevent thread galling, cross threading or other improper connection.
Unfortunately, conventional pipe compensation systems do not permit precise alignment between said pipe sections, while compensating for the weight of pipe sections hanging within a derrick. Moreover, said conventional pipe compensation systems do not permit optimal positioning and maneuvering during pipe stabbing and connection operations.